Blow-down system for boilers



Aug. 3,1937. H. H. WEED-EN 2,088,627

BLOW-DOWN SYSTEM FOR BOILERS Filed Sept. 12, 1935 INVENTOR If! Weed erg,

MQ/M

ATTORNEY Patented Aug. 3, 1937 UNITED STATES PATENT OFFICE Harry H. Weeden, Drexel Hill, Pa. Application September 12, 1935, Serial No. 40,250

1 Claim.

amended April 30, 1928; 370 0.

The invention relates broadly to-a system for blowing-down boilers and more particularly to a safety indication therefor.

'Inthe' present typeof boilers, possibility of the operator being scalded by coming into contact with water and live steam under high pressure when blowing-down a boiler is ever present. v Many of the boilers of the present type are designed to introduce the blow directly into a drain, and when this method is used the operator has no means of determining when a complete blowdown has been efiected because no provision is U made to indicate whether or not the water has passed through and steam is following. Other boilers are designed to allow the water to flow first into a funnel and then to a chain. This method is likewise unsafe to the operator because the drain may become clogged causing the water to rise in the funnel and overflow. A further method employed in other boiler designs is tofully enclose the top of the funnel. This method does not eliminate the element of danger to an operator, because, should the drain or sewer become clogged, a pressure will build up in the funnel sufficient tocause its destruction. Even though the funnel may be of sufficient strength to withstand the pressure imposed upon it, the uncertainty of knowing whether a blow-down is complete and whether all parts have a free and clear passage, is present. The entire operation is invisible, leaving a certain amount of guess work to the operator, which ultimately may lead to an explosion in the blow-down system.

One of the objects of the present invention is to overcome the above referred to disadvantages by providing visible or otherwise indication whereby an operator may be informed at all times of the actual condition in blowing-down a boiler. Another object of the invention is the provision of a receptacle for receiving the water and steam when a boiler blow-down system is exhausted, said receptacle being entirely enclosed to avoid any hazard to the operator.

Another object of the invention is to provide means permitting expansion of the blow-down pipes due to increase in pressure in the blowdo-wn chamber.

With these and other objects in view, as well as other advantages which may be incident to the use of the improvements, the invention consists of the parts and combinations thereof hereinafter set forth and claimed, with the understanding that the several necessary elements constituting the same may be varied in proportion and arrangement without departing from the V (01. 122 379) ,(Granted under the act of March 3, 1883, as G. 757) nature and scope of the invention as defined in the appended claim.

In order to make the invention more clearly understood there are shown in the accompanyingdrawing, means for carrying the invention into 5 practical effect,

without limiting the improvements in their'useful application tothe particular construction, which, for purpose of explanation, have been made the subject of illustration.

In the accompanying drawing: Fig. l is a side elevational view of a portion of a blow-down system of Fig; 2 is a sectional Fig. 1, and

a boiler;

view on the line 2-2 of Fig. 3 is a plan view of the structure shown in Fig. 1.

Referring to the drawing, an apparatus constructed in accordance with the invention is shown as comprising receptacle or bowl 4 having a body member 2| and a top member l6, secured together by suitable fastening elements l9 passing through flanges l1 and I8 provided on the cover and body members respectively, and an interposed packing gasket 20. The lower portion of the body member 2| opening communicating with a pipe 5.

The apparatus a sediment bowl B and each connected to the Il-9, and

I2--- I 0 respectively,

is provided with an outlet drain through a also includes a gauge glass A,

a feed. water regulator C, bowl by pipe lines 2-3, the flow through the lines being controlled by standard gate valves l. The pipes 3, 9 and I the receptacle through with flared ends l5 in I] extend downwardly into packing glands 6, l3 and are free to slide contraction due The H) are formed order to prevent their displacement from the glands 6, l3 and M. A pressure gauge 8 is mounted on the exterior of the receptacle 4 whereby the bowl are indicated.

fluctuations in pressure in A normally open check valve 1 is also mounted on the rear of the receptacle to provide a vent for steam entering the bowl in blowingdown a boiler.

When it is desired to blow-down a boiler, one

or more of the valves water from the gauge flow at boiler pressure through pipes l are opened, permitting glass A, for example, to- 2 and 3 into the bowl or receptacle 4, whence it will pass through the drain 5.

During the blow-down operation, a small amount of steam will rise from the water finding its through check valve 1.

way to the atmosphere As long as a small amount of steam is escaping through the check valve the operator knows that the system is functioning properly, but when a large amount of steam escapes, he knows that a complete blow-down has been effected. Steam will be visible to the operator as long as the water is carried off through the drain.

However, should the drain become clogged, pressure will build up in the receptacle closing the valve 1 shutting ofi the escaping steam, and at the same time this pressure will be indicated on the pressure gauge 8. The escaping steam causes an audible and visible indication, which if thus interrupted warns the operator of approaching danger in time for him to protect himself and/or the blow-down system by closing the valve or valves I.

As the gauge glass is usually placed some distance away from the receptacle 4, some expansion may be expected in the pipe lines due to the heat from the water passing therethrough. This expansion may take place in the present construction without causing damage to the elements of the blow-down system for the reason that the portions 3, 9 and M of the pipe lines are free to move through the packing tubes 6, I 3 and I4. Were it not for the bell-shaped or flared end 15 of the pipe 3, there might be a possibility of its being forced through the gland I3 by the increased pressure, thus endangering the operator.

Although I have described the operation of my invention in connection with the gauge water lass of a boiler, it is to be understood that when blowing-down the sediment bowl or feed-water regulator, the operation is the same.

It will be understood further that the above description and accompanying drawing comprehend only the general and preferred embodiment of my invention. and that various changes in details of construction, proportion andarrangement of parts, may be made within the scope of the appended claim without sacrificig any of the advantages of my invention.

The invention described herein may be manufactured and used by or for the Government of the United States of America for govenmiental purposes without the payment of any royalty thereon or therefor.

What I claim is:

Apparatus of the character described comprising a receptacle having an inlet for communication with a blow-down pipe of a steam boiler and an outlet for commimication with a drain, said blow-down pipe having a sliding connection with said receptacle to accommodate expansion and contractionof said pipe with changes in the temperature thereof and said outlet being of greater cross-sectional area than said inlet to prevent pressure from developing in said receptacle under normal conditions; a normally open check valve communicating with said receptacle for permitting the escape of steam to indicate when a blowing-down operation is completed and adapted to close under fluid pressure in said receptacle due to an obstruction in said drain; and means for indicating the fluid pressure in said receptacle.

HARRY H. WEEDEN. 

